Jul 1, 2006

Jeffrey M. Perkel

Invented in 1986 atomic force microscopy (AFM) has become a valuable tool for life scientists, offering the ability to image aqueous biological samples, like membranes, at nanometer resolution.

The technique is akin to reading Braille. Just as the blind read text by scanning their fingers across lines of text, AFM scans a material's topography using a tiny cantilever - a flexible projection, like a diving board, with a sharp, nanometer-sized probe tip protruding from the end.

Other variations on the technique are also possible: The technique can be used as a biophysical tool by measuring how much force is required to separate a ligand from a receptor. Alternatively, the AFM cantilever can be used as a pen to print biomolecular "nano-arrays," an application that at least two companies have commercialized.